Make the connection #4

Easy for you but not so easy for others, the problem is only 6 Cobra Daytona's were ever built, but I will give it a try, the 6 Daytona Coupes on the left where the cars ran by Alan Mann Racing for Shelby American to win the 1965 Championship over Ferrari and the four on the left were run by Shelby American in 1964 and lost the championship to Ferrari after Ferrari talked the FIA into canceling the last race of the season thereby giving the 1964 championship to Ferrari. Had the last race been run due to the performance of the Daytona over the Ferrari Shelby American would have more then likely won the 1964 championship as well. 

Having said all that I am probably out in left field and not even close to the right answer. 

@john3976 Here is a hint - back in the day you were assigned a number for every race

Whew! The pressure is on....   

There's NO WAY I have a chance but allow me to congratulate the winner in advance.  

@chris Sorry, I guess I was more esoteric with this one than I thought - The answer is they are all models of the same car chassis #CSX-2299. It was the second coupe built and the first of five built in Italy. It raced four times in 1964 - being first in class and 4th overall at Le Mans wearing the number 5. It raced six times in 1965 with class wins at both Daytona and Sebring and second in class at Le Mans.

It resides now at the Miller Museum in Utah repainted in its 1965 Daytona race trim

...all models have the same number ending in 2299, 2nd coupe of 5, but raced 4 times in '64, 1st & 4th and wearing #5, but 6 in '65 with class wins in 2 races... 

"2299, 2nd, 5, 4,'64, 1st, 4th, #5, 6, '65, 2" 

😯 😮 😯 😮 😲 😯 😲 😮 😲  

Frank, I'd say "esoteric"  is an understatement.  One not only needs to possess vast but exclusive Cobra build knowledge but also a mathematicians degree from MIT!  Yikes!

😏 😏 😏 🤔 🤔 🤔 🤨 🤨 🤨